Direct-acting antivirals and hepatocellular carcinoma in chronic hepatitis C: A few lights and many shadows

With the introduction of direct-acting antiviral agents(DAA), the rate of sustained virological response(SVR) in the treatment of hepatitis C virus(HCV) has radically improved to over 95%. Robust scientific evidence supports a beneficial role of SVR after interferon therapy in the progression of cirrhosis, resulting in a decreased incidence of hepatocellular carcinoma(HCC). However, a debate on the impact of DAAs on the development of HCC is ongoing. This review aimed to analyse the scientific literature regarding the risk of HCC in terms of its recurrence and occurrence after the use of DAAs to eradicate HCV infection. Among 11 studies examining HCC occurrence, the de novo incidence rate ranged from 0 to 7.4%(maximum follow-up: 18 mo). Among 18 studies regarding HCC recurrence, the rate ranged from 0 to 54.4%(maximum "not well-defined" followup: 32 mo). This review highlights the major difficulties in interpreting data and reconciling the results of the included studies. These difficulties include heterogeneous cohorts, potential misclassifications of HCC prior to DAA therapy, the absence of an adequate control group, short follow-up times and different kinds of follow-up. Moreover, no clinical feature-based scoring system accounts for the molecular characteristics and pathobiology of the tumours. Nonetheless, this review does not suggest that there is a higher rate of de novo HCC occurrence or recurrence after DAA therapy in patients with previous HCV infection.     

To stent or not to stent aortic dissection: good news for a chosen few, but who?

Eggebrecht and colleagues,¹ report their single centre experiencewith the interventional use of endovascular stent-grafts inthe setting of both chronic and acute thoracic aortic dissection,referred to or recruited by a group of cardiologists and followedup for between 1 and 57 months. The group at the West GermanHeart Centre in Essen confirm the reported feasibility and reporta high technical success rate for endovascular stent-graftingin the hands of skilled practitioners,^2–5 associated,however, with an 11% non-fatal periprocedural complication rate. Interestingly, though not surprisingly, multivariate analysisof their 38 cases revealed only parameters such as advancedage and poor health status     

Small hepatocellular carcinoma containing many Mallory bodies

Four cases of small hepatocellular carcinoma (HCC), consisting exclusively of Mallory body (MB)-containing cells, were presented. The MB-containing HCC cells seemed actively proliferating and infiltrated into the surrounding non-neoplastic tissue with a concomitant loss of the hepatic parenchyma, alpha-fetoprotein was immunohistochemically demonstrated in these MB-containing HCC cells. Therefore, the possibility arises that the process by which MBs are formed is a fundamental pathway that on some occasions may be linked with neoplastic transformation.     

Tumor suppressor and hepatocellular carcinoma

A few signaling pathways are driving the growth of hepatocellular carcinoma. Each of these pathways possesses negative regulators. These enzymes, which normally suppress unchecked cell proliferation, are circumvented in the oncogenic process, either the over- activity of oncogenes is sufficient to annihilate the activity of tumor suppressors or tumor suppressors have been rendered ineffective. The loss of several key tumor suppressors has been described in hepatocellular carcinoma. Here, we systematically review the evidence implicating tumor suppressors in the development of hepatocellular carcinoma.     

Pathophysiology of heparan sulphate: many diseases,few drugs

Heparan sulphate (HS) polysaccharides are covalently attached to the core proteins of various proteoglycans at cell surfaces and in the extracellular matrix. They are composed of alternating units of hexuronic acid and glucosamine, with sulphate substituents in complex and variable yet cell‐specific patterns. Whereas HS is produced by virtually all cells in the body, heparin, a highly sulphated HS variant, is confined to connective‐tissue‐type mast cells. The polysaccharides interact with a multitude of proteins, mainly through ionic binding, and thereby control key processes in development and homoeostasis. Similar interactions also implicate HS in various pathophysiological settings, including cancer, amyloid diseases, infectious diseases, inflammatory conditions and some developmental disorders. Prospects for the development of HS‐based drugs, which are still largely unrealized, are discussed.     

Biology of mitral valve prolapse: the harvest is big, but the workers are few

Mitral valve prolapse (MVP) represents a common degenerative disease, often requiring surgery. If untreated, MVP with considerable valve incompetence can lead to cardiovascular and systemic complications causing substantial morbidity and mortality.In contrast with the wide knowledge concerning clinical and physiological features, currently available data regarding its molecular bases are very limited.We review current knowledge concerning MVP biological mechanisms, focusing on specific aspects of haemostasis, platelet function, oxidative stress, extracellular matrix remodeling and genomics. In particular, available evidence supports the role played by tissue remodeling processes in determining MVP onset and progression. Moreover, even if a consistent although controversial perturbation of haemostatic system and alterations of the oxidative stress equilibrium have been proposed to influence disease development, it is unknown whether these changes precede or follow MVP occurrence. Consequently, the complete knowledge of all the biochemical pathways involved are far from complete.In addition, changes in the regulation pattern of adrenergic and renin-angiotensin-aldosterone systems have been described in MVP syndrome, a condition characterized by the association of MVP with other peculiar neurological and general symptoms, but it is unknown whether these abnormalities are shared by “traditional” MVP.In conclusion, MVP is probably a multi-factorial process, and many aspects still need to be clarified. As surgery can only correct the damaged valve but not the underlying mechanisms, a more complete knowledge of the involved molecular pathways is necessary, as it may allow the discovery of targeted therapeutic strategies aimed at modifying or slackening MVP natural course in the early phases.     

Tumor vaccine against recurrence of hepatocellular carcinoma

AIM: To investigate the effects of autologous tumor vaccine on recurrence of hepatocellular carcinoma (HCC). METHODS: Sixty patients with HCC who had undergone curative resection, were randomly divided into HCC vaccine group and control group. Three vaccinations at 2-wk intervals were performed after curative hepatic resection. Delayed-type- hypersensitivity (DTH) test was performed before and after vaccination. Primary endpoints were the time of recurrence. RESULTS: Four patients in control group and 6 patients in HCC vaccine group were withdrawn from the study. The vaccine containing human autologous HCC fragments showed no essential adverse effect in a phase II clinical trial and 17 of 24 patients developed a DTH response against the fragments. Three of 17 DTH-positive response patients and 5 of 7 DTH- negative response patients had recurrences after curative resection. After the operation, 1-, 2- and 3-year recurrence rates of HCC vaccine group were 16.7%, 29.2% and 33.3%, respectively. But, 1-, 2- and 3-year recurrence rates of the control group were 30.8%, 53.8% and 61.5%, respectively. The time before the first recurrence in the vaccinated patients was significantly longer than that in the control patients (P<0.05). CONCLUSION: Autologous tumor vaccine is of promise in decreasing recurrence of human HCC.     

Tumor suppressors and oncogenes in cellular senescence

Cyclin-dependent kinase inhibitors p16(INK4a), p21(Cip1), and p27(Kip1) are regarded as key effectors of cellular senescence. In this review, we describe three senescence-inducing pathways involving these inhibitors, namely, the p16(INK4a)/Rb pathway, the p19(ARF)/p53/p21(Cip1) pathway, and the PTEN/p27(Kip1) pathway. We emphasize the participation of tumor suppressors and oncogenes in the regulation of these senescence-inducing pathways. Finally, we discuss the impact of the Ras and Myc oncogenes on the above-mentioned pathways.